The Highlander

idespisecats · Mon Dec 11, 2006 4:33 pm

This is my second pneaumatic cannon. It uses a Cobbs valve (1.5 inch porting piston valve in a 2 inch tee.) It has 4" diameter 27" sch80 chamber and a 3" diameter 30" barrel. My first test fire I shot a t-shirt from my garage out of the end of my culdesack at 40 psi and nailed my neighbor's house. I'm currently porting it with a 1/4 in" ball valve, but I have plans to change over to a pneaumatically modified sprinkler valve(mostly to allow for it to be fired from the shoulder, it has plenty of power.) I also have plans on adding a breech to the barrel for easier loading. It's called the highlander because it's going to be used as a t-shirt launcher for my college and their mascot is the Highlanders. I also plan on giving it a nice paint job, maybe even a kilt paint pattern for the barrel. Tell me what you think.

pyrogeek · Mon Dec 11, 2006 5:26 pm

Looks good. What kind of air supply are you going to use? Or are they only going to shoot 1 shirt? I would suggest a small CO2 tank, like a 5LB with a regulator.

zeigs spud · Mon Dec 11, 2006 5:52 pm

i'd sugest the cheap easy way of air compresser. good job though!

noname · Mon Dec 11, 2006 6:42 pm

NEVER use ABS in pneumatics. Make a new barrel. It's not pressure rated and can and will eventually be ripped apart, causing it to be dangerous.

Zorrowannabe9 · Mon Dec 11, 2006 7:58 pm

I personaly dont believe using ABS as a barrel is any riskier than using PVC. The pressure is going to be in the barrel for a small fraction of a second. ABS does tear apart THAT easily.

Dom · Mon Dec 11, 2006 8:11 pm

Barrel seems to be fixed with the PVC fitting with PVC Cement.. BAD... REALLY bad.

SpudStuff · Mon Dec 11, 2006 8:22 pm

Just pop a few screws in the joint. You really do need to replace that barrel. It WILL rip apart. I have has a ABS barrel on a combustion rip. That produces a maximum of 75 PSI for ~1/10 of a second. That is NOT safe. If you spent the money for a SCH 80 chamber.(unnessary) Buy the barrel.

ProfessorAmadeus · Mon Dec 11, 2006 8:29 pm

its especialy useless with regular sch 40 fittings. But over all this is a good cannon. Did you buy the valve for the talon guy? If you could, get a new barrel then get one. A few extra dollars is well worth peace of mind knowing that it wont explode.

idespisecats · Tue Dec 12, 2006 1:19 am

the chamber is sch80 just because I happenned to have some left over from something else. I'll put those screws in though. I won't be firing over 70 psi so I'm not worried about the barrell blowing up one me.

TalonXxX · Tue Dec 12, 2006 4:18 pm

Yes, ProfessorAmadeus I supplied him with that loverly valve

at a very fair price I might add. Anyone else interrested I'd be more than happy to make one for your needs.

$40... probably like $50-55 shipped to you and it packs quite a punch for a 2" valve. I has full 1.5' porting and o-ring piston and therefore has great actuation... making it that much more powerful.